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1.
Children's perceived attachments with parents, and family cohesion and adaptability were examined as predictors, mediators, and moderators in the parental problem drinking-child outcomes link. A total of 216 6- to 12-year-olds (110 boys, 106 girls) participated. Data were obtained from children and their mothers, fathers, and teachers. A higher level of family cohesion and adaptability functioned as (a) a robust protective factor against adjustment and cognitive difficulties otherwise associated with problem drinking and (b) a mediator of adjustment problems. Children's perceptions of attachments to mothers and fathers were consistent predictors of behavioral, social, and cognitive problems and further moderated relations between problem drinking and child functioning. The results support that child-parent and family functioning variables act as either pathways and/or vulnerability and protective factors for children exposed to a high-risk environment. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
2.
本对影响轻型轨道车下道装置操作性能的液压系统参数进行了分析,对29.4kW走行发电轻型轨道画下道装置中的手动液压泵的结构参数进行了优化设计,与初定参数进行了比较,并对方案设计进行了修正。  相似文献   
3.
This paper uses sliding mode control to accomplish the objectives of swing‐up and stabilization of the cart‐pole underactuated system. The features of underactuated systems prohibit direct application of conventional sliding mode control for fully‐actuated systems. In this paper, we design a novel sliding mode control for the cart‐pole underactuated system so that the control goals can be achieved. In addition, by simply changing the parameters of the sliding surface, we use only one sliding mode control scheme to swing up and to stabilize the cart‐pole system. Using the sliding mode dynamics and the internal dynamics, we show that the proposed sliding mode control can swing up the cart‐pole system from the stable equilibrium and can stabilize the system to the unstable equilibrium. Our simulation results on a cart‐pole system demonstrate the feasibility of the proposed sliding mode control. The proposed control schemes, the stability analysis, and the numerical simulation provide a useful guideline for designing the sliding mode control for the cart‐pole underactuated system.  相似文献   
4.
针对电子商务的发展和企业网上销售自主产品的需求,设计了一个基于B/S模式的医药在线支付系统,分析了在线支付的多种方法、支付流程以及安全支持,根据系统需要选择可靠的支付手段,分析了系统在实施过程中出现的主要问题并初步提出相应解决方法,并对主要模块进行了具体的设计和实现。  相似文献   
5.
This research investigated mothers' affect in the context of children's homework. Mothers (N=109) of children 8 to 12 years old were interviewed daily about their affect while interacting with children, their assistance with children's homework, and children's behavior while completing homework. At this time and 6 months later, children's motivational and emotional functioning was assessed. Although mothers' negative affect was lower than their positive affect, it was elevated on days their assistance with homework was high. This was accounted for by mothers' perceptions of children as helpless on days they provided heightened assistance. Mothers' positive affect in the homework context buffered children's motivational and emotional functioning against mothers' negative affect as well as children's helplessness. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
6.
Comparative optimism has been studied extensively in adults and is a significant component of social- cognitive models about health. In contrast, little is known about comparative optimism in children or about the wider social- cognitive processes that underpin their health-related behavior. This study investigated comparative optimism for health- and nonhealth-related topics in 101 children 8 or 9 years of age, the youngest ages that have been investigated so far. Children were shown to be unrealistically optimistic for health and nonhealth events. The implications of these findings for understanding comparative optimism in children are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
7.
8.
《Ergonomics》2012,55(6):735-746
Pushing is an important materials handling activity in many occupations; however, pushing-related physiological investigations are still in infancy. The purpose was to evaluate maximum acceptable forces and physiological responses while pushing on: treadmill (TREAD); plywood floor (PLY); and Teflon floor (TEF). Acceptable forces, cardiopulmonary and calf muscle oxygenation and blood volume responses were collected simultaneously while 12 men (age 39 ± 13 years; height 178 ± 6 cm; and body mass 91.5 ± 16 kg) pushed for 2 h on each surface at their psychophysical workload. Participants selected higher forces on the PLY, resulting in higher pulmonary oxygen uptake compared to that of TEF (by ~9%) and TREAD (by ~18%). Pushing on the TEF demonstrated 50–56% lower blood volume changes and 1.5–1.8 times more oxygenation-force ratio than that for other surfaces. It is concluded that, to avoid a potential slip, participants were conservative in selecting acceptable forces to push on the slippery TEF. Part of this compensatory strategy on the TEF resulted in less muscle activity and, therefore, less demand for oxygen delivery to the calf muscle than for other surfaces. The present findings of significant force- and physiological-related differences in treadmill vs. high inertia pushcart clearly demonstrate that pushing experiments are essential to evaluate functional abilities of the workers.  相似文献   
9.
孙振宇  刘江  沈高云 《轮胎工业》2003,23(12):722-726
对国产IIR 175 1、俄罗斯ΒΚ 1675N、日本JSR2 68三种牌号的IIR在力车轮胎内胎中的应用进行了研究。结果表明 ,3种牌号IIR内胎胶料的门尼粘度、硫化特性和工艺性能相近 ,硫化胶老化前和老化后 ( 12 0℃× 48h)的物理性能差异不大 ,成品内胎的物理性能和耐久性能均达到国家标准。 3种牌号的IIR均可用于力车轮胎内胎的生产 ,但IIR 175 1价格低 ,货源稳定 ,更具竞争力  相似文献   
10.
针对儿童房设计与装修的重要性,从绿色环保、设计与布置、缤纷的色彩和充足的照明等方面探讨了儿童房的设计与装修,以提高儿童房的设计质量,从而为儿童创造美好的生活居住环境.  相似文献   
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